DC-DC converters are used for a broad variety of applications and devices, in particular battery driven hand-held and portable applications. Some devices require several different voltages or currents for different parts and functions of the device. One example for such device is a cell phone with an integrated camera module, where a constant voltage may be required for the regular cell phone functions and a high current for the flash light of the camera. A conventional approach provides an individual DC-DC converter stage with individual regulation loops for each function. However, this approach is expensive, power consuming and bulky.